Pump mechanism



2 Sheets-Sheet 1 ammer )Yi/ns e.

Oct. 4, 1932. s. wlLTsE PUMP MECHANISM Filed June 9. 1927 Oct. 4, 1932.s, wlLsE I ,1,881,012

PUM MECHANISM Filed June 9. 1927 2 Sheets-Sheet 2 l 72192 .l @ya 58 Yfra.

.Sumner )Yi/1156.

Patented @et 4, 1932 erica SUMNER WILTSE, OF DETROIT, MICHIGAN,ASSIGNOR, BY MESNE ASSIGMENTS, T

' EVANS APPLIANCE COMPANY,

A CORPORATION on MICHIGAN PUMP MECHANISM Application led June 9,

' rllhis invention relate-s to pump mechanism and particularly to acombined oil and fuel pump for internal combustion engines, the

principal object being the provision of apuni- Y 5 tary oil and fuelpump simple in construction, economica-l applied. f Another object ofthe invention is to providey a combined oil and fuel pump in whichcorresponding ends of a pair of housing inembers are each provided witha chamber for receiving one rotor of a pair of aligned rotors, eachrotor terminatingin substantially the piane of the end of the housing inwhich it is received; the rotors are driven by acommon line of shafting;Y and the housing of one chamber closes the chamber provided in theother. l Y

Another object isto provide al combinedoil and fuel pump comprising ahousing enclosing a sliding vane type pump element, a second housingenclosing' a similar pump ele- 'ment the vane-s of which are disposed atright-angles to the varies in the first pum g to Y manufacture andeasily g5 element and which housing closes the first housing', asubstantially Hat cap and cover lbeing provided for thesecond` housingenclosing a by-pass pressure relief valve for governing the maximumpressure capableof being` builtup bythe second pump element.

Another Objectis to provide a unitary oil and fuel pump comprising asingle pair of rotors suitably housed and driven by aligned shafting,parts of which are suitably connectedtogether for equal rotation, aby-pass pressure relief valve operated by the outlet pressure of thefuel pump beinglprovi'ded for maintaining the pressure of the fuel asdelivered to the carburetor at less than a pre-v determined maximumvalue.

Another object is to provide in combination with an internal combustionengine, a fuel pump positioned within the crankcase thereof, whereby thefuel passing through the same will absorb heat from the crank caseA andwill result in a more economical and smoother running engine. K

'A furtherobject is to provide in combination with an internalcombustionengine, a

sm f

:1.1 unitary'mechanically ldriven oil and fuel 1927. k'senin No.197,753.

pump provided with a common member therebetween, and operated within thecrank case of the engine in such a position as to come in Contact withthe oil therein whereby the fuel passing through the pump will be heatedboth by radiation of heat in the crank case and by conduction of heatfrom the oil pump part ofthe mechanism through ythe common member.

' The above being among the objects of the present invention, thesame'consists in certain features of construction and combinations ofparts to be hereinafter described with reference to the accompanyingdrawings, and then claimed, having the above and other `objects in view.

In the accompanying drawings which illustrate a suitable embodiment ofthe present invention, and in which like numerals refer to like partsthroughout the several different views,-

Fig. l is a vertical sectional view taken transversely through aninternal combustion engine provided with a unitary oil and fuel pumpwithin the crank case thereof.

Fig. 2 is an enlarged side elevation of the combined oil and fuel pumpshown supported within the crank case of the engine in Fig. l. v y

Fig. 3 is a vertical sectional view taken transversely of the oil pumpshown in Fig. 2 as on line 3 3 of Fig. 2. v

Fig. 4 is a horizontal sectional view taken on line 4 4 of Fig. 2showing the rotor 4and y on line y6 6 of Fig. 2 showing the rotor and'sliding vanes constituting the moving parts of the fuel pump of thepresent invention.

Fig. 7 is a View taken on line 7-7 of Fig. 2 being a plan view of thecover secured to the lower face of the pump.

Fig. 8 is a sectional view taken through the cover shown in Fig. 7 as online 8-8 of Fig. 7, illustrating y,the by-pass pressure relief valvemechanism. n

The present invention is an improvement :01 discharge pipel 35.- leadsfrom VtheY oil dison the construction shown and described in myapplication for Letters Patent of the United States for improvementsin'pumps filed April 181511,1927, serial No. 184,573.

In accordancewith the present invention I have shownlnFig. 1 an internalcombus- -tion enginey provided withV aunitary crank case upper half andcylinder blocky 10, cylinder head'11 and crank case lower half or oilpan 12: Rotatably i supported within the crank case of.` the engine is acrank'. shaft 13j connected by the conventional connecting rod 14 tothepiston 15 which is adapted to reciprocate within the cylinder 16,`formed within the cylinder block l0v upon rotation'` ofthe cra-nkshaft.13. The cylinder-16 1s connected bythe combustion chamber 117 tothefintake port 18 which in tur-n is connected ytothe intakejmanifold 19which'. is provided with thensual carburetor 20. A valve 2l ispositioned to-close the port 18 and is actuated by the cam 22 formedionthe rotatable cam shaft 23 'through the tappet 24.,v A spi` ral bevergear 25 secured onthe camshaft` 23m-eshesfwith another suitable spiralgear 26secureidf'tofthe vertically extending shaft 27 ,suitably`supported. at its upper end by the bearing 28. Secured to the side ofthe crank case 10by bolts129 or other suitable rmeansyisgabracket30whichfextends down into the lower part ofthe oil pan 12andremovably receives therein: acombined oil and fuel pumpy formedl in'accordance withf'the presentinvention..

l A tube 31- connects the carburetor 2.0 vwith the fuel discharge sideof'this pump-mecha*- nism, the tube 31f'passi'ngl through the crankcase*- upper half` 10', whichv isv sealed-1' against' leakagearoun'd'thesame by means of a nipple such as32.y Af similartube33connecting` p the; fuel'rintake side of. the pump mechanismwith'arsour'ce of fuel supply, such as a; gaso- Vlfineatanlr (notshown), passes thro'ughthe crank case upper half 1() andl is sealed vagainst. leakagefby means ofa nipple' similar togni'pple 32 shown/"inconnection with Atube` 31. A short tube 34 connects-thel oil inlet.

sidexof' thev pump mechanism with' the space inthe'fbottom ofthe" oilpanV12 andan oil charge side of the pump'unechanism tothe various'bearingsof the engine. v

Asillustrated'in Figs. 2'to18 inclusive,- the pump` mechanism comprisesa housing 36 providedwith externallbearing. portions and; 38Y adapted tobe removably' clamped within? thelower'v en'di of the bracket; 30;Withinzthe housing' 36- and' opening into the bottom face thereof isarecess 39 circular in section. Positioned within the recess 39eccentricall'ythereof is a rotor' 40 provided with a hub 41V extendingupwardly.l into the casi-ng 36`-andprovidedfwith a suitable bear.- ingtherein. ,A shaft 42 extending; axially down through the housing 36 andprovided with a suitable bearing in the upper portion thereof, isloosely received within the hub 41 and is looked against relativerotation in respect thereto by the pin 43 whichloosely passes throughtheshaft 42. The lower end of the shaft 42 is provided with a tongue 44,

the purpose of which will presently be de-V scribed.

Secured tothe lower face 'of the housing 362by'means of the screwsl45isa second housing 46 closing the open end of the recess 39.

-Thelower face of the housing 46 is provided with a recess 47 similar tothe recess 39, and

a rotor48 similar to the rotor 40 is positioned leccentric-ally therein,.a shaftv 49 being loosely secured to the rotor 481andfextendingupwardly throughy the housing 46, 'whereit is,`

providedV with. a suitablebearing surface in axial alignment with .theshaft42: YThe upper end of the shaft 49 is slottedandv projects upthrough the rotor where'it is loosely re.- ceived and slidablylengagesthe tongueV 44 formedv on the :lower end of the shaft 42. A. cap50 is shown. assubstantially hat, eX- cepting as if itis shaped toforma; valved bypass with thin metal cover 51'; and, a spacer member. 52being 'optionallyA interposed, said cap' andcover may be secured to thelower faceof the housing 46 by meansvof screws such as 53.. Y

The rotor 40is provided withV a transverse slot 54 extending across thediameter thereof in alignment withthe tongue. 44 and for the full depthof the rotor 40,4 and slidably `Vreceived within. the slot-54 are twovanes 55. Positioned between the vanes 55 is aspring 5G which constantlyurges the vanes 55 outward-v lyinto contactwith the side walls oftherecess 39.y The projectin@ ends ofthe vanes 55 are bevelled offinthedirection` of rotation Vwhich is indicated by the arrow in Fig.. 4 forsubstantially the'fullwidth of the same, for a purpose ltobedescribedlater. The rotor 40 isV of such. a diameter that the periphery thereofslidably engages thefside wall ofthe recess 39v on the line-indicated as`5'( in Figi. 4. v

Formed within the-walls'of 'therecess 39 on eitherV side of the line 57f is the; inlet port58 and outlet yport 59., VThe inlet port-158 isconvided, with va transverseslot. 63 yof similarV character to the slot54previously described inl connection withthe rotor 40, and whichslidably receives the vanes 64 which are shaped similarly to the vanes55 and which are beveled off in the same manner and in the samedirection, a suitable spring 65 being provided for constantly urging thevanes 64 apart and into Contact with the side walls of the recess 47 yIt is to be particularly noted that the axial line of the vanes 55 andthe axial line of the vanes 65 are at right-angles to each other, thisfeature being provided in order to equalize the `turning resistancebetween the same to provide a quieter running mechanism,and reduce thewear.

The rotor 48 contacts with the'side walls of the recess 47 along theline indicated as 66 in Fig. 6, in the same manner as the rotor 40contacts against the side wall of the recess 89, and formed in the sidewalls of the recess 47 on either side thereof is the intake port 67 andoutlet port 68, the inlet port 67 being `connected by the passage 69with the exterior face of the housing 46 and to which passage 69 thefuel inlet pipe 33 is adapted to be suitably secured. The outlet port 68eommuni- Cates with the exterior face of the housing 46 by means of thepassage 70 which is adapted to be suitably connected to the tube 81extending from the same to the carburetor. Openings 71 and 72 connectthe ports 67 and 68 with the lower face of the housing 46, and openings7 3 and 74 may be formed in acooperating part such as the mentionedcover member 5l between the cap 50 and housing 46 and in alignment withthe openings 7l and- 72. Formed in the upper face of the cap 50 andextending between the openings 7 3 and 74 is a ymentioned by-passpassage 75 which passage is shown as completed by said cover member andas enlarged below the opening 74; and received therein is a coil spring76. A disc 77 of larger diameter than the opening 74 and slidablyreceived in the enlarged end of the passage 75 is shown as illustratingone type of valve element suitable to be constantly urged by the spring76 upwardly against the under face of the member 5l in which position itcloses the opening 74l from the passage 75. l f

Formed within the upper face of the housing 46 as indicated in Fig.v 5',is a groove 78 extending from the discharge port 59 to the bearing forthe shaft 49 wit-hin the housing 46, the same groove being provided forconducting oil under pressure to the bearing in order that the same mayprovide a seal between the recesses 39 and 47. If desired,circumferential grooves such as 79 (see Fig. 8) may be provided in thebearing for the shaft 49 in order that oil may be conducted thereto fromthe passage 78 and better seal the recesses 39 and 47 from each otheragainst the passage of fuel. Y

The operation of the device will be apparent from the above'descriptionwhich, stated shortly, is as follows:

Upon rotation of the cam shaft 23, the gear 25 secured thereto is causedto rotate and in turn causes rotation of the gear 26 secured to theshaft 27. The shaft 27 is provided with a suitable type of sleeve jointat its lower end, provided with a tongue (not shown) which slidablyengages the groove in the upper end of the shaft 42, thus causingrotation of the shaft 42. In rotating, the shaft 42 carries with it therotor 40 which, as before eX- plained, is mounted eccentrically in therecess 39. In rotating, the vanes 55 seal the space between the rotor 40and the side walls of the recess 39 and slide inwardly and outwardly ofthe slot 54 in order to accommodate the variation of the of the rotor 40and the side wall of the recess 39. As each vane 55 rotates past theintake port 59 it creates a suction back of it, thus causing the oil tobe drawn through the port 58 between the rotor 40 and side wall recess39 and between the vane 55 and the line of contact 57, the succeedingvane 55 causing this oil to follow around each of the first mentionedvanes 55, and as soon as the first menwithin the'slot with their outerends in contact with the side walls of the recess 47 in eX- actly thesame manner as the vanes previously described in connection with therotor 40, causing the fuel to be drawn in through the port. 67anddischarged through the port 68. It is to be noted that the passages 7land 72, openings 73 and 74, and the closed passage 75 form a continuouspassage which, but for the valve disc 77, would allow fuel forced out ofthe port 68 to immediately return to the intake port 67, thus preventingany pressure from being built up in the fuel pump. The spring 76 isprovided for controlling this return flow of fuel between the ports 67and 68, it being so proportioned that until the maximum desirablepressure is built up in the discharge passages of the fuel pump, thedisc 77 will remain seated and close the opening 74, butis so designedthat as soon as this maX- imum desired pressure is built up, the disc 77will be acted upon by such pressure, and will be moved away from theplate 51 thus allowing the excess fuel to flow from the port 68 throughthe passage 75 and back to the intake port 67.

Inasmuch as the volume of fuel pumped by space between the outer edgethis type of pump varies in proportion to the yspeed-of the same, itWill be'apparent that in order to obtain the necessary fuelrequirements-atlow speeds of the engine thata pump V5 must' be providedWhich will supply a volume of;fuel at high speeds greatly in excess ofthe amount needed. In order to prevent the press'ureonthe discharge sideof the pump from building up over the desired maximum presimsurefvvhichfory fuel pumps is seldom over one and one-half to two pounds, theopenings 73., and 74 andthe. passage? 5 are designed with ampledimensions to. prevent anyy lappreciable restriction in the flow of fueltherethrough aty high speeds so that there Will be n determinedpressures, the vanes recede slightly from the 'Walls of thecorrespondingr'ecesses 39 and 47, thusaiding in slightly reducing thepressure built up, andin receding from the Walls of the recessessubstantially eliminatevvear on the ends of the varies.`

' It will be recognizedthat leakage of fuel past the shaft 49 andintothe oil pumprecess the lubricating oil Whichfmight lead to seriousresults. In order to prevent such a possibility, theV groove .78 isprovided for conducting voilfrom the discharge port 59 of the oil pumpvto the bearing for the shaft 49 in the housing 46. Because of thesuperior pressure of the lubricating oil, a small amount of such oil isforced int'o'con'tact vviththefshaft 49, and not only serves tolubricate thev same in its bearing in the housing 46, but also providesan effective sealfor preventing leakage of'fuel therepast. f f

As above described,fthe shaft'42 is providedwith a relatively closefitting bearing in the upper end of the hous'mg 36 and is looselyreceived Within the hub 41 of the rotor 40 which hub is provided with arelatively close bearing Within the lower portion of the housing 36.Thisprovides a construction very'ec'onomical to manufacture inasmuch asno particular pains need toV be taken for perfectly aligning thebearings for the shaft 42 and the lhub v41, and but tvvo relativelyclose 'fits are necessary for the same. ln addition,

Vnofparticularly accurate machinework is required at'y this point. Thegroove Within the upperfend ofthe shaft 49 may be suitably l relieved sothat, the vanes 55 slidaloly passing, 6?, through' the same arefreeofany tendency to 39 would allowcornmingling .of the fuel With;

the shaft 49 loosely receives the tongue 44 and bind therein, and noparticular precision is necessary in connecting the housings 36 and 46together. Y j Y A particularly important feature of the presentinvention Vis the positioning of the mechanism within the lower kparteof the oil pan l2,`and preferably below the normal level 8O of the' oiltherein. The advantages Yrealized. by this feature of the invention arelthat the fuel passing through the'pumping mechanism is heated and amplelubrication is provided forthe bea-ring` for the shaft 42 therethroughpassesdovvn through the housling 46, heating the same, and causing thefuel passing therethrough to be heated. The

housing'46 and'cap 50, Wherethe same are positioned above the norma-llevelof the fuel, are also heated by the spray of oil from the bearingslof the engine, which comes in contact With the same. By thus heating thefuel being fed to thecarburetor 2O more complete vaporization of thesame is obtained with the resulting. smoother and more economicalperformance of the engine. I

Formal changes'may be Vmade inV t-hey spe-l ion cie embodiment of theinvention described n Without departing from the' spirit and'substanceof the broad invention, the scope of which is commensurate With theappended claims. v

What I claim is; p Y

l. A fuel and oil pump having, in combination, anoil pumpcasing, saidcasinghaving a pump chamber eXtendingto an end thereof, Vsaid casinghavingan oil inlet and an voil outlet communicating with the chamber, anoil pump rotor'bearingin the casing, said Yoilpump rotor having ya bore,and having an end in substantially the same planeas the correspondingend of said casing, a drive shaftin the bore non-rotatably connected tothe oil pump rotor, afuel pump casing so formed and attached tothe oilpump casing as to close the mentioned chamber, the fuelv pump Vcasinghaving an inlet opening, a pump chamber extending to the correspondingend thereof, and an outlet opening, a fuel pump rotor terminatingsubstantially in the plane of said corresponding lend and bearing inthe` fuel pump casing, lsaid fuel pump `rotor having a bore, and adriven-shaft non-rotatably connectedatV one end Vto the'fuel pump rotorand extending atthe other end f into the oil pump chamber andnon-rotatably connected chamber and being a single line of shafting tothe drive shaft, and a substantially flat cover for the fuel pumpchamber.

2. The combination in claim 1 in which the fuel chamber is provided witha cap which contains a duct and has a relief valve therein, an aperturedcover being interposed beneath saidrcap, and said duct leading from theinlet to the outlet of the, chamber, whereby to bypass the fuel upon anoverload.

3. A pump structure comprising a pair of approximately aligned pumpcasings hav ing pump chambers formed therein, a partition separating thechambers, a pump rotor in each chamber, a shaft interconnecting the tworotors, each end of the shaft being slotted and one slotted endprojecting into one of the rotors and a transversely disposed impellerblade extending outwardly from the outer peripheryof said one of therotors and being disposed in the last-mentioned slotted end of theshaft.

4. A pump structure comprising a pair of approximately aligned pumpcasings having pump chambers formed therein, a rotor disposed in eachchamber, a shaft connecting the two rotors, one end of the shaft beingslotted and extending through an opening in one of the rotors and beingengaged by a tongue upon a drive shaft, said slot also receiving animpeller blade extending transversely through the last-mentioned rotor.

5. In combination: an oil pumpl comprising a housing which provides apump chamber at an end thereof and a single rotor disposed in saidchamber and terminating in the plane of said end; a fuel pump comprisinga housing having an inlet opening and an outlet opening and a singlerotor, an end of the last mentioned housing cooperating with the firstmentioned housing to close the oil pump provided in its other end withan additional chamber; a substantially flat cap for closing saidlast-mentioned chamber; cooperating parts embodying a by-pass pressurerelief valve for said fuel pump; and for driving both of said rotors, atongue and slot being respectively provided for cooperation at adjacentends of parts of said shafting and a vane of said oil pump beingslidably received in said slot.

SUMNER WILTSE.

